Turning off IPV6 in Karmic

A very effective and clean way to set it off for those experiencing issues due to IPV6, mostly old routers are not compatible and therefore all your DNS queries get delayed.

sudo gedit /etc/sysctl.conf (sudo kate in case you are in KDE)

Add the lines
#
# disable ipv6
net.ipv6.conf.all.disable_ipv6=1

reboot and enjoy faster browsing, its always a good idea to use namebench to measure for best DNS servers in your locality and use those, usually Google's DNS is doing well in most but there are faster ones as I found out in my case, I add PDNSD to the system where frequently used dns are cached to the disk leading to very quick and fast lookups.

A very effective and clean way to set it off for those experiencing issues due to IPV6, mostly old routers are not compatible and therefore all your DNS queries get delayed.

sudo gedit /etc/sysctl.conf (sudo kate in case you are in KDE)

Add the lines
#
# disable ipv6
net.ipv6.conf.all.disable_ipv6=1

reboot and enjoy faster browsing, its always a good idea to use namebench to measure for best DNS servers in your locality and use those, usually Google's DNS is doing well in most but there are faster ones as I found out in my case, I add PDNSD to the system where frequently used dns are cached to the disk leading to very quick and fast lookups.

Yep this is when you have firewall iptables enabled, the method I mention above is to disable ipv6 from kernel level where its compiled in Ubuntu, both should work, the former will need iptables enabled by default, in Ubuntu, its not enabled and since I use a router, I keep it disabled as well.

Works fine here, the cat /proc/net/if_inet6 returns nil whereas before this setting it would give me data, also network tools now reports ipv6 as unknown and before it gave me a scope 64 reading. This method is the easiest to implement, the other method is to add the disable ipv6=1 to grub command line.

Works fine here, the cat /proc/net/if_inet6 returns nil whereas before this setting it would give me data,

Click to expand...

It returns nil here too, but I still have services listening on tcp6 and udp6.

This method is the easiest to implement, the other method is to add the disable ipv6=1 to grub command line.

Click to expand...

I have done both methods, and still have services listening. It probably isn't working for you either (have you ran sudo netstat -tupvnl to check for tcp6 and udp6 services)?

As I said, Ipv6 is compiled statically into the kernel. You have to reconfigure the kernel and then recompile it in order to turn it off. Why the Ubuntu devs decided to do this instead of compiling it as a module, I don't know.

Guess you are not doing something right here. Even if its in listening state, there is no active connection established in your case and no dns query sent out by your browser via IPV6 so its an effective mod.